The present invention relates to a handling section for an endoscopic treatment tool that is used as it is passed through the treatment tool insertion channel of an endoscope.
Endoscopic treatment tools generally have a handling section, a flexible sheath the basal end of which is coupled to the handling section, and a manipulating wire which passes through the flexible sheath to be movable back and forth relative to the flexible sheath.
The basal end of the manipulating wire is coupled to a manipulating member movably provided in the handling section so that the manipulating wire can be moved back and forth through the manipulating member.
If the manipulating wire of the endoscopic treatment tool is pushed into the flexible sheath in a more-than-necessary amount, it buckles to break. A stopper is therefore necessary that restricts the range over which the manipulating wire is pushed into the flexible sheath.
A conventional way to meet this need is shown in FIG. 6; a step 93 is defined within a basal end socket 95 of a flexible sheath 94 to serve as a stopper which is brought into contact with the distal end of a drive rod 92 securely coupled to the distal end of a manipulating wire 91.
A problem with this design is that if the length of the flexible sheath 94 is increased to about 2 m as in the treatment tool used with a colonoscope, the difference between the lengths of the flexible sheath 94 and the manipulating wire 91 is so great as to cause variations in the manipulation stroke S.
If the manipulation stroke S is unduly short, the manipulating wire 91 does not work properly; if the stroke is excessively long, the manipulating wire 91 buckles to break. The same phenomenon occurs if the manipulating wire 91 extends as the result of repeated use of the treatment tool.
Handling sections for endoscopic treatment tools are also characterized in that even ones of an identical type are commonly used with many and various types of treatment tools and that the manipulation stroke S has to be set in accordance with the specific models of such treatment tools. To meet this requirement in the conventional handling section for endoscopic treatment tools that is described above, the position in which the drive rod 92 is secured to the manipulating wire 91 has to be changed but this involves a very complicated operation.
An object, therefore, of the present invention is to provide a handling section for an endoscopic treatment tool that permits the manipulation stroke of a manipulating wire to be set or changed to an optimal condition in an easy way.
This object can be attained by providing a tubular stopper for restricting the range over which a manipulating member is moved to push a manipulating wire member into a flexible sheath. The tubular stopper is detachably fitted to the basal end portion of the flexible sheath such that the tubular stopper is loosely fitted over the manipulating wire member. If necessary, the stopper is removed, has its length changed and is replaced, whereupon the manipulation stroke of the manipulating wire member can be easily set or changed to an optimal condition.
In a preferable embodiment, a handling section for an endoscopic treatment tool includes:
a main body to which a basal end of a flexible sheath is detachably coupled;
a manipulating member to which a basal end of a manipulating wire member is detachably coupled, the manipulating member being movably arranged on the main body to axially move the manipulating wire member relative to the flexible sheath; and
a tubular stopper detachably coupled to the basal end of the flexible sheath and fitted over the manipulating wire member, the tubular stopper restricting a range over which the manipulating member is moved in a direction in which the manipulating wire member is pushed into said flexible sheath.
The tubular stopper is preferably formed of a nonmetallic material that can be cut with a cutter, such as a flexible tube.
The present disclosure relates to the subject matter contained in Japanese patent application No. Hei. 10-308145 (filed on Oct. 29, 1998), which is expressly incorporated herein by reference in its entirety.